Logical pluralism is the view according to which there is more than one relation of logical consequence, even within a given language. A recent articulation of this view has been developed in terms of quantification over different cases: classical logic emerges from consistent and complete cases; constructive logic from consistent and incomplete cases, and paraconsistent logic from inconsistent and complete cases. We argue that this formulation causes pluralism to collapse into either logical nihilism or logical universalism. In its place, we propose a modalist account of logical pluralism that is independently well motivated and that avoids these collapses.

According to modalism, modality is primitive. In this paper, we examine the implications of this view for modal epistemology, and articulate a modalist account of modal knowledge. First, we discuss a theoretical utility argument used by David Lewis in support of his claim that there is a plurality of concrete worlds. We reject this argument, and show how to dispense with possible worlds altogether. We proceed to account for modal knowledge in modalist terms.

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David Lewis defends Genuine Modal Realism (GMR) by way of an inference to the best explanation (IBE); reasons of theoretical utility are taken as markers of truth. Warrant for thinking that IBE is reliable depends on the availability of access to the relevant matters that is independent of the various uses of IBE. Domains permitting no such independent access are domains over which we can have no confidence that instances of IBE are reliable. Genuine Modal Realism's plurality of worlds is one such domain. The wider implication is that IBE is not reliable for adjudicating metaphysical disputes.

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